iterationStart property of
AnimationEffectTimingReadOnly represents which repetition the animation begins at and its progress through it.
// Getting the iterationStart var animationStartingPoint = animation.effect.timing.iterationStart; // Setting the iterationStart animation.effect.timing.iterationStart = 5.9;
A floating-point value whose value is at least 0 and is not
+Infinity, indicating the offset into the number of iterations the animation sequence is to run at which to start animating.
iterationStart represents the iteration index at which the animation effect begins as well as its progress through that iteration.
Usually you'll use a value between 0.0 and 1.0 to indicate an offset into the first run of the animation at which to begin the animation performance, but any positive, non-infinite value is allowed. Since all animations' iteration indexes start at 0, a value of 0.5 would start the animation halfway through its first iteration or loop. Meanwhile, a value of 1.2 means the animation will begin playback 20% of the way through its second iteration, and so forth.
It's currently undefined what happens if you specify a value of
iterationStart which is greater than the value of
AnimationEffectTimingProperties.iterations. See issue 170 in the Web Animations API specification's issue tracker for details and status of any changes to the specification in this regard.
The definition of 'AnimationEffectTimingReadOnly.iterationStart' in that specification.
|Working Draft||Editor's draft.|
|Feature||Android webview||Chrome for Android||Edge mobile||Firefox for Android||Opera Android||iOS Safari||Samsung Internet|
|Basic support||?||?||?||451 2||No||No||?|
1. The preference is set to
true by default on Firefox Nightly and on Firefox Developer Edition, but not on the official release.
2. From version 45: this feature is behind the
dom.animations-api.core-enabled preference (needs to be set to
true). To change preferences in Firefox, visit about:config.